New boss Manuel Pellegrini has been busy during the summer transfer window, and that has seemingly resulted in Cullen dropping down the pecking order at the London Stadium.
The 22-year-old has previously spent time on loan in the Championship, and the midfielder has acknowledged that a similar deal could potentially be struck in the coming weeks.
Cullen told the London Evening Standard: "There have been conversations going on. It's not that I've decided totally whether I am staying or going. At the minute I'm here, just taking each day as it comes and trying to impress the manager.
"First and foremost I want to be playing for West Ham, but if the manager says to me 'there's the right loan there' then I'll go and get some games up until January, come back and look at it then."
Cullen has made nine first-team appearances for West Ham, while the opening half of the last campaign was spent on loan at Bolton Wanderers.